Dogs are very sensitive animals when it comes to sniffing out anything fishy or that which is not palatable. In fact, some dogs survive poisoning and then develop this ability to detect the same poison in food even in small quantities. Dogs can treat drugs as belonging to this category because not only do they have an unpleasant taste but they also have some side effects ranging from nausea to sweating. I suppose the best method is not to crush the pill and mix it with food as many people are won't to do. This is because this will increase its surface area and make it easier to detect. The best plan is to coat or embed the silk in steak and them give it to the dog. I don't suppose a bolus gun would work with a dog because they are prone to stress and fear and this would not be humane thing to do.